To increase efficiency of fifth generation (5G) cellular networks, a concept was suggested which is based on a layered transmission of access information (see, e.g., “A Clean Slate Radio Network Designed for Maximum Energy Performance” by p. Frenger et al., presented on the IEEE 25th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), Washington, D.C., Sep. 2-5, 2014). In this concept, user equipments (UEs) are provided with access information by using broadcasted access information tables (AITs) and a broadcasted system signature sequences (SSSs), where each SSS may be used to identify information from the broadcasted AIT. The AIT may for example define settings concerning a how a UE shall access the system, e.g., by a random access procedure, concerning how the UE can be reached by the system in a paging procedure, or concerning more advanced settings, such as related to beam forming or link adaptation. The AITs are typically transmitted with long periodicity, while the SSSs are typically transmitted more frequently. Typically each access node (e.g., a base station) will transmit an SSS which allows the UE to identify the information applicable to this access node from the AIT. The AITs do not need to be transmitted by every access node. For example, a base stations serving a macro cell may transmit both an AIT and an SSS, while a base station serving a small cell within a coverage region of the macro cell may transmit only an SSS. Accordingly, the AIT will typically include entries applying to various access nodes, which means that the AIT may have considerable size.
The size of the AIT may result in high radio resource usage and energy consumption for broadcasting the AIT. On the other hand, the information from the AIT required by different UEs may vary. For example, some UEs may need only basic information from the AIT, e.g., parameters for controlling a random access procedure or a paging procedure, while other UEs may require further information from the AIT, e.g., parameters for controlling beam forming.
Accordingly, there is a need for techniques which allow for efficiently distributing access information in a cellular network.